The present invention relates to a transverse guide roller track-guidable vehicles and, more particularly, to transverse guide rollers which effectively prevent the access of water to a rotational bearing of the rollers.
Transverse guide rollers are generally known as shown, for example, in German Offenlegungsschriften 2,636,656; 2,641,637; 2,935,386; and 3,704,512. A common feature of these transverse guide rollers is that the rolling bearing necessary for the rotational bearing for the horizontally aligned transverse guide roller is sealed by a horizontally disposed seal which, in turn, is overlapped by a stationary disc to prevent the access of coarse dirt particles. Although this cover disc can prevent the access of coarse dirt particles into the seal, it cannot prevent the access of water. Specific operating conditions and treatment for such transverse guide include water splashing up when driving through puddles, flooding when driving through very deep puddles, spraying with a high-pressure jet when cleaning the vehicle, in particular in the region of the wheel guards, and melting of snow lying on top.
As a result of these treatments and conditions, water can also penetrate a labyrinth in the region of the disc overlapping the seal and reach as far as the seal protecting the rolling bearings. Although the seals are watertight, at least when new, an underpressure builds up inside the bearing when the bearing, warm from operating, cools down, the underpressure sucks water lying outside the seal into the inside of the bearing.
In addition, dirt is also brought, together with the water, into the region of the sealing lips, and exerts an abrasive action and adversely affects the seal over time. As the structural space accommodating the rolling bearings has been closed from beneath by static seals, the water which has penetrated can no longer leave through the bottom, so that the bearing fills with water after a relatively short time. This greatly affects the lifetime of the bearings. In the event of frost, water which has penetrated also results in the complete suppression of the bearing function because the water which has frozen to form ice effectively preventing the rolling bearing from rotating. The transverse guide rollers grind along the road-side transverse guide webs and are ground flat very quickly. Repair then becomes essential within a very short time.
An object of the present invention is to improve such a transverse guide roller and its bearing, so that the damage encountered in conventional constructions can be reliably avoided and a relatively long lifetime of the bearings can be expected.
This object has been achieved according to the present invention by widening a journal which supports the transverse guide roller in a bell-shaped fashion to form a bearing bell which covers the entire rolling bearing arrangement from above and receives an outer ring of the roller bearing. The wheel body can be designed in the shape of a cup with an upwardly pointing opening and with a bearing journal projecting from the cup bottom on which the inner ring of the roller bearing is fixed.
As a result of the arrangement of the rolling bearing inside a bell closed at the top, under the conditions stated above, it is normally impossible for water to get as far as the locations of the rolling bearings because they are overlapped from above by closed walls which extend as far as the underside of the rolling bearing. Nevertheless, should water, in the event of flooding, have access to the location of the bearing, this water can immediately flow out downwards, by gravitational force through discharge orifices provided at the lowest point in the cup bottom, before being able to cause any damage to the bearing. Sprayed water which penetrates the guide roller runs over the outside of the bearing bell and flows out again at the bottom at the discharge orifices.